Friction is used to refer to forces that resist relative motion, in general,whereas viscosity refers specifically to resistive forces that occur between layers of a fluid when fluids attempt to flow. Fluid friction is the force that resists the movement of a solid object through a fluid(liquid or gas). Sky divers falling down through the sky experience a type of fluid frictioncalled air resistance.
Answer:
speed is affected by the medium in wich the wave travels.
Explanation:
The speed of a wave is affected when traveling in different medium, depending on the medium in which the wave travels it can go faster or slower, or not even be able to travel in that medium.
For light waves, the denser the medium through which the wave travels, the slower it will go through it, as there is more resistance to the light particles.
And in waves like sound, which instead of particles is a vibration or disturbance in the medium, they travel faster in denser mediums such as metal, because the disturbance is transmitted more efficiently thanks to how close together that the particles are in the metal, This is why sound does not travel in a vacuum; there are not even particles to transmit the vibration.
A galaxy is a system of millions to billions of stars, and is held together by gravitational attraction. There are around 2 trillion galaxies.
Answer:
it may be efficient at first but over time there will be a lot of wasted energy.
Explanation:
I'm pretty sure
Answer:
The answer is 
.
Explanation:
You are asking only for the total volume, so the important data here is the surface area of the earth's crust,
and the average thickness of the earth's crust,
.
Imagine that you can stretch the surface area as if it were a blanket, now if you want to calculate its volume, you just need to multiply its area by its thickness,
.
